The invention relates to an electric motor having a measurement system for determination of the position or movement of a first motor part which can move with respect to a second motor part, wherein the second motor part has a number of magnetic field sensor devices which are separated from one another along the movement direction.
The electric motors may be linear or rotary motors.
Known measurement systems have the common feature that discrete position indicators are arranged at uniform intervals in the movement direction in which the position is to be determined, and are read by a single read head. In the event of a movement, the position can be determined by suitable evaluation of the read signal, for example by incremental logic. The accuracy of the position determination is in this case governed by the distance between the position indicators.
Because of the spatial extent of the position indicators in the movement direction, these distances cannot be reduced indefinitely, however, and, furthermore, the manufacturing effort is increased for measurement systems with miniaturized distances.